Coffee maker



Feh 2Q, 1945. E. WALDER ETAL 2,370,096

COFFEE MAKER Filed Nov. 12, 1942 Patented Feb. 20, 1945 UNITE COFFEEMAKER Emil Walder and Joseph W. Myers, Philadelphia, Pa, assignors toProctor & Schwartz, Inc., Philadelphia, Pa, a corporation ofPennsylvania Application November 12, 1942, Serial No. 465,346

4 Claims.

This invention relates to coffee makers, and more particularly to coffeemakers of the wellknown vacuum type which employ a filter element toprovide a clear beverage.

In the past, coffee makers of this type have employed filter elementsutilizing fabric material or the like to filter or strain the coffeebeverage as it is drawn downward into the lower vessel. Such devices areobjectionable for a number of reasons, among which are the following.

It is difiicult to cleanse the filter element. and no matter howcarefully and thoroughly this element is cleansed, it will in timeaffect the flavor of the coffee.

Such a filter element is unsanitary due to its construction and mannerof use.

The filter element must be replaced periodically, not only for the abovereasons, but also because it deteriorates with use, and itsdeterioration is aggravated by the necessary frequent washing of theelement.

The periodic replacement of the element not only involves inconvenience,but also involves the expenditure of money as well.

The principal object of the present invention is to provide an improvedcoffee maker of this type which eliminates the above-mentionedobjections and disadvantages.

Another object of the invention is to provide, in such a coffee maker, anovel filter device which is easy to clean and is sanitary, and whichdoes not adversely affect the flavor of the coffee beverage and does notrequire replacement.

A still further object of the invention is to provide a device of thischaracter in which a compressed body of the ground coffee is utilized asthe filtering means.

Other objects and features of the invention will appear hereinafter.

In the accompanying drawing:

Figure 1 is an elevational view, on a small scale, of a vacuum typecoffee maker embodying the present invention;

Figure 2 is a sectional view of the coffee maker; and

Figures 3 and 4 are perspective views of the two vided with a suitablehandle 8, and a lid 4 serves to close the top of the upper vessel 2. Thecoffee maker is used in conjunction with a suitable heater 5.

Referring to Fig. 2, the vessel 2 has the usual tubular portion 6extending downward into the vessel i and adapted to conduct liquidbetween the two vessels. In operation of this type of coffee maker, thewater i in vessel l is heated and rises upward through the tube 6 intovessel 2, as indicated by the full line arrows. In the upper vessel 2,the heated water comes into contact with the ground coffee 8, and theinfusion of the two forms the coffee beverage. When substantially all ofthe heated water ha risen into the vessel 2, the applied heat is shutoff, and the vacuum created within vessel i draws the coffee beveragedownward through the filter device, as indicated by the broken linarrows.

In accordance with the present invention, there is provided a novelfilter device 9 which is adapted to contain a predetermined quantity ofground coffee in compressed state. As shown more clearly in Figs. 3 and4, the filter device comprises two parts iii and ii. Part i0 is in theform of a shallow cup-like container having a foraminated base, whilepart it is-in the form of a foraminated lid or cover for the saidcontainer. The container ii] is such size and shape that it will receivea predetermined quantity of finely ground coifee when it is filled to aline or plane level with its upper edge. Preferably, the container isadapted to receive one unit of the ground coffee, as will be more fullylater.

The parts it and ii are provided with cooperative means for securing thecover I i in place and also for causing the cover to compress the groundcoffee within the container l8. Such means comprises outwardly extendingprojections IL on container it and inwardly extending projections i3 oncover l I. These elements are arranged so that the projections l3 may beinserted in the spaces between projections 12, and the cover Il may thenbe rotated to interlock the said projections. Th lower surfaces ofprojections l2 are inclined, as shown in Fig. 4, to provide cam surfaceswhich cause the cover ii to exert pressure on the coffee within thecontainer it). To this end the cover is slightly dished, as shown inFig. 2, and it is provided with a relatively long handle is having agripping knob at the end thereof.

The container it carries a resilient sealing ring and it also carries aspring member i'i whose ends areslidably interiitted as shown at it.This spring member H, which is preferably formed of resilient metal, maybe secured to container it by means of a rivet i9 or the like. The lowerportion of vessel 2 is formed to provide a horiaontal annular surfaceupon which sealing ring it may seat and to provide a recessed portion2:) corresponding in cross section to the shape of the spring member I!and adapted to receive the latter. When the filter device is in place,as shown in Fig. 2, it is permitted to move upward slightly by virtue ofthe resilience of spring H. The purpose of this will be explainedpresently.

A sealing member 2| is provided between the upper part of vessel i andthe lower portion of vessel 2, as is customary in such devices.

In using the coffee maker, the user first places the desired quantity ofwater in vessel I and then inserts the empty vessel 2-in place, with thelid 4 removed. The user then fills the container ID with finely groundcoffee, removing any excess coffee above a level with the upper edge ofthe container. The cover Ii is then applied and rotated as describedabove, thereby compressing the ground coffee as shown at 22 in Fig. 2.This operation is facilitated by the handle 14 and its knob IS. The userthen inserts the filter device within the vessel 2, forcing the springmember ll into the recessed portion 20 of vessel 2. The freedom of theends of the spring member to slide relative to one another permits theinsertion of the spring member as described. The user then places enoughground coffee within vessel 2 to provide the necessary total quantityground coffee for the desired quantity of beverage. For example, if thequantity of beverage desired requires four units of ground coffee, oneunit will be placed in the filter device, while three units will beplaced in a loose state in the vessel 2, as illustrated.

In operation, the heated water rises through tube 8 and exerts an upwardforce on the filter device, causing it to rise slightly, as shown inFig. 2. Substantially all of the rising water passes about the filterdevice, since the compressed body of coffee within the filter devicepresents high resistance to the passage of the water therethrough.However, the compressed ground coffee within the filter device becomesmoistened and swells, thereby compressing this coffee to an even greaterextent. The upward stream of water passing through the small spacebetween the slightly raised sealing ring 16 and the wall of vessel 2prevents the loosely ground coffee from moving downward.

When substantially all of the water has risen into vessel 2, the filterdevice is lowered into sealing relation with the wall of vessel 2 by theaction of spring member i1 and the weight of the water and of the deviceitself. As the coffee beverage is drawn cownward by the vacuum in vesselI, it is forced to pass through the filter device. The compressed Jodyof finely ground coffee within the filter device serves as a veryefficient filtering means, with the result that the beverage is entirelyfree of any ground coffee.

After the coffee has been made, as described above, the user removes thefilter device from vessel 2 and then removes the cover ll of saiddevice. The codes within the container [0 is compressed into asubstantially solid state and may be readily removed by rinsing under afaucet.

The speed of filtering varies to some extent inversely with the degreeof compression of the ground coffee within the filter device. Theclarity of the filtered beverage also varies to some extent directlywith the degree of compression. Thus an increase in filtering speed maybe obtained, at some sacrifice of the degree of clarity, by turning thecover H less than the usual amount, which results in a lesser degree ofcompresslon of the ground coffee.

From the foregoing description, it will be seen that, the inventionprovides a novel apparatus for making coffee which eliminates theobjectionable features of prior coffee makers of this type and hasvarious advantages as hereinbefore set forth. The filter device providedby the invention may be constructed of any suitable material. Forexample, the principal parts of this device may be formed of Bakelite,plastic, or other suitable material, while the sealing ring [6 may beformed of rubber or the like.

It will be understood that the invention is not limited to the specificform of the device illustrated, but is capable of modification withinthe scope of the appended claims.

We claim:

1. In a vacuum type coffee maker, a water heating vessel, 9. coffeeinfusion vessel adapted to receive loose ground coffee, said infusionvessel being disposed above said water heating vessel during operationof the coffee maker, said infusion vessel having a tubular portionextending downward into said water heatin vessel for transferring liquidbetween the vessels, a. foraminous container adapted to receive andcompress a relaitvely small predetermined quantity of ground coffee, andadapted to be disposed in the lower part of said infusion vessel and tonormally close the upper end of said tubular portion, and means for s6securing said container in position as to permit the same to rise underthe pressure of heated water rising in said tubular 85 portion, wherebysubstantially all of the rising water passes around said container intodirect contact with the loose ground coffee in the infusion vessel, andsaid container then closes the upper end of said tubular portion forcingthe coffee beverage to pass through the compressed ground coffee in saidcontainer to filter the bev- 2. In a vacuum type coffee maker, a. waterheating vessel, a coffee infusion vessel adapted to receive loose groundcoffee, said infusion vessel being disposed above saidwater heatingvessel during operation of the coffee maker, said infusion vessel havinga tubular portion extending downward into said water heating vessel fortransferring li uid between the vessels, the water rising through saidtubular portion when heated and creating a vacuum in said water heatingvessel which draws the beverage downward, a foruminous container adaptedto receive and compress a quantity of ground coffee, and adapted to bedisposed in the lower part of said infusion vessel above said tubularportion, and means for causing substantially all of the rising heatedwater to pass around said container into direct contact with the looseground coffee in the infusion vessel, and for causing the coffeebeverage to pass downward through the compressed ground coffee in saidcontainer under the impetus of the vacuum formed in said water heatingvessel, thereby to filter the beverage.

3. A vacuum type coffee maker as defined in claim 2, wherein saidcontainer comprises two parts, and attachment means therefor includingcam surfaces which effect compression of the ground coffee within thecontainer.

4. In a vacuum type coffee maker, a water heating vessel, a coffeeinfusion vessel adapted to receive loose ground coffee, said infusionvessel being disposed above said water heating vessel during operationof the coffee maker, said iniuslon vessel having a tubular portionextending downward into said water heating vessel for transferringliquid between the vessels, said infusion vessel also having a recess atthe upper end of said tubular portion and below the body portion of thevessel, a foraminous container adapted to receive and compress arelatively small predetermined quantity of ground coffee, and adapted tobe disposed in the lower part of said infusion vessel and to normallyclose the upper end of said tubular portion, and a spring member securedto the bottom of said container and adapted to seat in said recess, saidspring member serving to secure said container in position andpermitting the same to rise under the

